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<blockquote cite="mid:20090820122224(dot)GA5532(at)merkur(dot)hilbert(dot)loc"
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<pre wrap="">In other words, I have a conversion table of all different units. If
there is no conversion between 2 units (such as volume and area) then
the sum returns null.
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Shouldn't that return NULL IOW unknown ?
Karsten
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I am not familiar with returning unknown. I know that according to the
spec an aggregate should only return null if all of its values of the
aggregate are null. If there is a way to return unknown in a non-NULL
way, then that would be preferred.<br>
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